GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Bromus laevipes

HABIT Perennial. Culms decumbent; 30–150 cm long; rooting from lower nodes. Culm-internodes distally glabrous, or pubescent. Culm-nodes pubescent. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs scanty, or lacking. Ligule an eciliate membrane; 2–4.2 mm long; lacerate; obtuse. Leaf-blades 13–26 cm long; 4–10 mm wide; light green, or glaucous. Leaf-blade surface smooth, or scaberulous; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; secund; 10–20 cm long. Primary panicle branches ascending, or spreading, or drooping.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 5–10 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 23–35 mm long; with hairs extending 1 mm beyond apex, or 3 mm beyond apex; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; shorter than spikelet. Lower glume lanceolate; 6–9 mm long; membranous; without keels; 3 -veined. Upper glume lanceolate; 8–12 mm long; membranous; without keels; 5 -veined. Upper glume surface scabrous.

FLORETS Fertile lemma oblong; 12–16 mm long; chartaceous; without keel; 5 -veined. Lemma surface pubescent. Lemma margins ciliate; hairy below. Lemma apex awned; 1 -awned. Principal lemma awn subapical; 4–6 mm long overall. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 3.5–5 mm long. Ovary with a fleshy appendage above style insertion; pubescent on apex.

FRUIT Caryopsis with adherent pericarp; hairy at apex.

DISTRIBUTION North America: northwest USA and southwest USA.

NOTES Bromeae. Pavlick 2004.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.